Optical techniques represent a valuable tool for non-invasive investigation of in vivo tissue properties and imaging of tissue structures. Diffuse light reflected from a tissue contains not only information on the properties of the tissue surface, but also information on tissue structures residing at depths of several millimeters. Such information is important for several clinical situations, e.g., in determining the depth and size of Port-wine stain vessels, the thickness of nodular basal cell carcinoma or the depth of necrosis in a burn. The aim is to develop a non-contact, near-infrared technique for tomographic mapping of a tissue surface with information of tissue properties to depths of 5-10 mm. This kind of information is important for establishing a proper protocol for various clinical modalities. One example can be to determine the depth of nodular basal cell carcinomas, where this information of depth is important for determining a proper drug and light dose for photodynamic therapy, or for cryotherapy. Another example can be in treatment of burns, where the depth of necrosis and the blood perfusion has to be determined. The project will be based on available expertise in photon migration work present at the Beckman Laser Institute and the Norwegian Institute of Technology. The first phase of the work will aim to develop specific and optimized algorithms and subsequently test/verify the theoretical results on equipment which, has already been developed, in part, at the Beckman Laser Institute. Provided that the results from this first phase are satisfactory, a second phase can be initiated where the algorithms and the technical equipment will be optimized for various applications.